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101.
In the newborn, cerebral pial arteriovenous malformation has been recognized as a cause of congestive heart failure. Prenatal diagnosis allows early medical treatment of cardiac failure and increases the chance of successful neuroradiological intervention. This paper highlights the importance of careful prenatal cerebral examination in cases of cardiac ventricle enlargement.  相似文献   
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For the clinical application of cultured human mesenchymal stem cells (MSCs), cells must have minimal contact with fetal calf serum (FCS) because it might be a potential vector for contamination by adventitious agents. The use of human plasma and serum for clinical applications also continues to give rise to considerable concerns with respect to the transmission of known and unknown human infectious agents. With the objective of clinical applications of cultured human MSCs, we tested the ability of autologous plasma, AB human serum, FCS, and artificial serum substitutes containing animal-derived proteins (Ultroser G) or vegetable-derived proteins (Prolifix S6) to permit their growth and differentiation in vitro. To conserve as much autologous plasma as possible, we attempted to mix it at decreasing concentrations with the serum substitute containing vegetable-derived mitogenic factors. Under control conditions, by day 10 all the fibroblast colony-forming units (CFU-Fs) were alkaline phosphatase (ALP) positive. However, their number and size were highly variable among donors. Better CFU-F formation was obtained with Ultroser G, and with human AB serum and autologous plasma mixed at, respectively, 5 and 1% with Prolifix S6. The effects of these mixtures on CFU-F formation demonstrate synergy, with the human serum or plasma supplying the factors that favor differentiation of MSCs while Prolifix S6 supplies the mitogenic factors. Finally, we demonstrated the possibility of controlling human MSC growth and differentiation in vitro. Notably, by means of a minimal quantity of human serum or human plasma mixed with a new serum substitute containing vegetable-derived proteins, we displayed growth and differentiation of human MSCs comparable to that obtained with FCS or serum substitutes containing animal-derived proteins. These results will have crucial significance for future applications of cultured human MSCs in bone tissue engineering.  相似文献   
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The diagnosis of prostate adenocarcinoma is usually made on needle biopsies. Numerous benign lesions may mimic malignancy, especially when the focus of carcinoma is limited. The presence of seminal vesicle-ejaculatory duct epithelium on prostate biopsy is not rare and could cause confusion with adenocarcinoma. Lipochrome pigments are frequently encountered in seminal vesicle-ejaculatory duct but may be also seen in prostate adenocarcinoma. Prostate specific antigen immunostaining in difficult cases is sometimes used, but high-grade adenocarcinomas may be negative. In one previous report, MUC6 was found to be expressed in seminal vesicle but not in normal prostate. MUC6 belongs to the family of human mucin genes. So we investigated herein the immunohistochemical expression of MUC6 in prostate adenocarcinomas and seminal vesicle-ejaculatory duct. We have tested 30 prostate adenocarcinomas of various grade, 10 normal seminal vesicles, and 10 prostate adenocarcinomas invading the seminal vesicles. The tissues were fixed in 10% buffered formalin and embedded in paraffin. Immunohistochemistry was performed using the avidin-biotin-peroxidase complex technique. All adenocarcinomas and normal prostate structures tested were negative. In contrast, all seminal vesicles were diffusely immunostained with MUC6 antibody. We concluded that MUC6 is a valuable marker of seminal vesicle-ejaculatory duct and is useful for the differential diagnosis with prostate adenocarcinoma.  相似文献   
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Frequent deregulation of cyclin-dependent kinase (CDK) activation associated with loss of cell cycle control was found in most of human cancers. A recent development of a new class of antineoplasic agents targeting the cell cycle emerged as a small molecule CDK inhibitor, roscovitine, which presents potential antiproliferative and antitumoral effects in human tumors. Additional studies reported that roscovitine combined with cytotoxic agents can cooperate with DNA damage to activate p53 protein. However, little is known about the biological effect of roscovitine combined with ionizing radiation (IR) in human carcinoma, and no studies were reported thus far in p53 mutated carcinoma. In the breast cancer cell line MDA-MB 231, which lacks a functional p53 protein, we found a strong radiosensitization effect of roscovitine in vitro by clonogenic survival assay and in vivo in MDA-MB 231 xenograft model. Using Pulse Field Gel Electrophoresis, a strong impairment in DNA-double-strand break rejoining was observed after roscovitine and IR treatment as compared with IR alone. Cell cycle analysis showed a G(2) delay and no increase in radiation-induced apoptosis in the cells treated with IR or roscovitine and IR. On the other hand, we found a significant induction in micronuclei frequency after roscovitine and IR treatment as compared with IR alone. This effect was also observed in BALB murine cells in contrast to SCID murine cells, which are deficient in DNA-PKcs, suggesting a possible DNA-double-strand break repair defect in the nonhomologous end joining pathways. In MDA-MB 231 cells, the radiosensitization effect of roscovitine was associated with an inhibition of the DNA-dependent protein kinase activity caused by a marked decrease in Ku-DNA binding by using the electrophoretic mobility shift assay. In conclusion, we found a novel effect on DNA repair of the CDK inhibitor roscovitine, which acts as a radiosensitizer in vitro and in vivo in breast cancer cells lacking a functional p53.  相似文献   
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The Abl tyrosine kinase inhibitor imatinb is becoming a standard for the treatment of chronic myelogenous leukemia (CML). However, Bcr-Abl gene mutations have been reported mainly in relapsing or resistant patients. In primary resistant patients, only few mutations have been documented so far, suggesting alternative mechanisms. We aimed to investigate if alpha 1 acid glycoprotein (AGP), an acute phase drug binding protein, could be a biological marker for pharmacological resistance to imatinib in nine patients in acute phase CML. All patients (3/3) with high AGP dosages (2.31+/-0.17 mg/mL; normal values, 0.5-1.3mg/mL) were primary resistant to imatinib whereas an early clinical response was observed for the six patients with normal AGP levels (1.13+/-0.2mg/mL). No mutation in the adenosine triphosphate domain of Abl were detected before the initiation of imatinib therapy. By using in vitro tests combining various imatinib concentrations (1-10 microM) with purified human AGP (1 and 3 mg/mL), we demonstrate that imatinib-induced apoptosis of K562 or fresh leukemic CML cells is abrogated or reduced. The same effect was observed using sera from donors with high AGP levels (1.9-3.28 mg/mL). In patients with CML in blastic phase, AGP levels could reflect pharmacological resistance to imatinib, suggesting that increased dosage of imatinib or the use of a competitor to drug binding should be recommended to optimize the therapeutic effect of the drug.  相似文献   
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